[i430FX] PC Partner MB500N won't boot DOS 6.22 with three or four IDE HDDs

[usergithub64]

Describe the bug [i430FX] PC Partner MB500N does not boot DOS 6.22 with three or four IDE HDDs. With one or two IDE HDDs, DOS 6.22 boots fine.

To Reproduce Steps to reproduce the behavior:

1. Create machine [i430FX] PC Partner MB500N
2. C/H/S Parameters: 1054/16/63 (518MiB)
3. Connect a system HDD with DOS 6.22 and three more IDE HDDs to the built-in IDE controller
4. Set the BIOS parameters HDD Type: AUTO, Mode: AUTO (as in the screenshot below)
5. Start the machine, about 30 seconds after the HDD is detected, you will see the message "Hard disk(s) fail (80)" (as in the screenshot below)

Expected behavior DOS 6.22 should boot normally with three or four IDE HDDs

Desktop (please complete the following information):

• OS: Windows 10 Pro x64 v21H2
• 86Box v3.7.1 x64 Build 4051
• Build type: regular, old recompiler.

[Cacodemon345]

Award BIOSes don't support more than 2 HDDs.

[OBattler]

It's an 86Box bug because it used to work fine.

[OBattler]

Now it works fine with 3 hard disks, but still fails with 4 hard disks - same behavior as on the ECS, so it appears to be an Award 4.50PG bug. As such, I'm closing this.